Exhaust purifier



June 24, 1930. w. RIEHM EXHAUST PURIFIER Filed March 15, 1926 IN VENTOR.

' We ATTORNEYS.

Patented June 24,1930

UNITED STATES PATENT? OFFICE WILEELM RIEHM, OF AUGSBUZRG, GERMANY,ASSIGNOR TO THE FIRM: MASCHINEN- IAIBRIK AUGSBUBG-NUERNBEBG,AK'IIENGESELLSCHAFT, OF' AUGSIBU'RG, GER- MANY, A GERMAN CORPORATIONnxnaus'r roan-Inn Application filed March 15, 1936, Serial No. 94,875,and -in Germany February 6, 1926.

. operated by heavy oils, there is frequently a poor combustion, whichis due to the fact that there is not sufiicient time for securing acomplete combustion of the heavy hydrocarbons. In consequence thereofthe exhaust will become of disagreeable odor, which will beobjectionable to the public and eventually bring the owner of thevehicle in conflict with the laws.

This invention has for its object to avoid this drawback and to do awaywith the disagreeable odor of the exhaust gases. The invention consistsessentially therein, that suitable catalyzers are arranged in theexhaust container, which bring about an aftercombustion of the exhaustgases. For this purpose catalyzers consisting, for instance, ofiron-oxide are associated with the exhaust container in such a mannerthat the exhaust gases will have to pass through the same. he exhaustgases, in addition, thereby heat up the catalyzer to such an extent thatan after-combustion will be brought about, so that the still unburnthydrocarbons will undergo combustion and the exhaust gases dischargingfrom the exhaust container will become practically free of color andodor.

For the proper efficiency of the catalyzer it is absolutely requiredthat the temperature is kept at a value as high as possible. It may,however, happen that during some longer time of operation at small loadsor during zero load the temperature of the catalyzer by reason of thelow temperature of the exhaust gases will become so low that asufficiently quick after-burning of the heavy hydrocarbons can no longertake place. In order to keep the catalyzers in such case in eflicientcondition, according to this invention, there are means provided whichcause said catalyzers to be maintained at the required temperature. Inorder to accomplish this, for instance, the drawn-in combustion air ispre-heated before entering the working cylinder, which may be done bythe exhaust gases themselves. Also, for this purpose the combustion airmay be choked off, so that the drawn-in quantity of air will bedecreased corresponding to the small-,

er charge of the fuel.

In the drawing an exhaust container according to this invention isshown, Fig. 1 being a longitudinal section of said exhaust container andFig. 2 showing the exhaust container in connection with the combustionengine.

he device according to this invention 0011- sists of a cylindricalvessel or container 0,, which'surrounds the end of the exhaust pipe I).The latter carries a number of closed screens or sieve-like bodies 0,which are arranged in spaced relation to each other, said screens orforaminous bodies being filled with a catalyzer d, for instanceiron-oxide. The several screens or sieve-like bodies are arranged inpairs between the screen bores 6 provided on the exhaust pipe I) saidbores serving for the discharge of the exhaust gases. The screens orsieve-like bodies a are again surrounded of sheet metal f, in such amanner that one of such jackets is provided for each pair of screens.The several jackets f surrounding the several pairs of screens 0 are soarranged with respect to each other, that a small interstice or gap 9 isformed between successive jackets. In order to secure the severalscreens in proper position with respect to the exhaust pipe I), a bolt71 is employed by which said screens are fastened to the cover it of theexhaust container aand braced against one another by means of spacingmembers j.

The exhaust pipe 6 is closed up at its free end by a cover is, saidcover being pivoted to a double lever m which is kept under tension bythe spring 11..

The exhaust gases will pass in closed condition of the cover isthrough-the bores e into the free space between the screens 0, and becarried thereupon through the catalyzers d which are heated thereby tosuch an extent that the unburnt hydrocarbons which are still containedin the subsequent exhaust gases will undergo combustion. The exhaustgases are thus freed of color and odor and will pass through theinterstices or gaps g into the exhaust container 01, whence they aredischarged to the outside through the exhaust 0. 1

In order to maintain the temperature of .the exhaust gases, which isrequired for an eflicient working ofthe 'catalyzers, at the propervalue, as in case of smaller loads of some:duration or in case of zeroload there are two suction inlets q and rdprovided on the cylinder ofthe engine, sai suction 1nlets being connected with each other by theconduit .9. The exhaust conduit t passes through the suction inlet 1*,so that the air, which is drawn-in by this inlet, will be preheated. Anysuitable form of preheater may be used, and such a one is discloseddiagrammatically in the drawing 1n which the exhaust passage 10 from thecylinder discharges into the interior chamber 11 of a double-walledcylindrical container t, the space between the inner wall and the outerwall of the container 1? forming a passage 12 through which' airentering through the A inlet 1- passes to be heated, and thence passesby the passage 8 to the intake passage 13 of the cylinder. The exhaustgases escape from the interior chamber 11 o the preheater 27 through 'acentrally arranged pipe 14 which communicates withthe chamber 11, thepipe 14 being connected with exhaust pipe 15 which in turn is connectedto the exhaust container a. Throttle valves u and v are provided withinthe suction inlet g and the conduit 8, said throttle valves beingdisplaced relatively to each other by an angle of 90 degrees. Thethrottle valves u and '0 may be interconnected by suitable linkageindicated diagrammatically at 21, and r0- vided with an operating rod 22exten ing to a convenient point for manipulation by the operator atwill. During normal load of the engine the throttle valves u and a)being adjusted as shown in Fig. 2, the suction inlet 1' is inoperativeand the engine will draw-in cold exterior air through the suction inlet9. The air is drawn through intake passage 13 past inlet valve 16 intothe combustion space of Diesel engine cylin- 'der 17 on the suctionstroke of the piston 18. This air is then compressed on the compressionstroke of piston 18 to a high pressure and temperature such thatspontaneous ignition of fuel injected through nozzle 19 is secured atsubstantially the end of the compression stroke. .This produces aworking stroke of piston 18, and on the succeeding upstroke of thepiston the products of combustion escape past exhaust valve 20 into theexhaust passage 10. If the load of the engine drops or becomes zero, sothat also the temperature of the exhaust gases will drop below the valuerequired for the efficient working of the catalyzers d, the valves u and'v are reversed so that now the suction inlet 9 will be closed, thecombustion air entering the suction inlet 0*, thereby passing theexhaust conduit t, by which it will be preheated. If it is desired notto employ this last described arrangement, the average temperature ofthe cyhnder may also be maintained at its normal value by closing the'valve 0 and only partially opening valve u, so that a smaller quantityof air corresponding to the smaller quantity of fuel will enter thecylinder. o

If it is desired to put the exhaust contamer out of operation, which mayfor instance be the case outside of cities or other inhablted places,the cover is is lifted from its seat by adjustin the lever m by the aidof the adjusting ro p. By this the exhaust pipe 1; W111 be opened andthe exhaust may immediately discharge through the outlet 0 provided onthe exhaust container a, without being forced to first pass thecatalyzers d.

I claim:

1. An exhaust container for an internal combustion engine comprising acasing havmg an outlet, an exhaust inlet pi e projecting into saidcasing, a plurality o spaced screens positioned about said exhaust inletpipe, a acket surrounding said screens and spaced from the inner wall ofsaid casing, catalytic material arranged within said screens, saidexhaust pipe and said jacket having openings respectively arranged instaggered relation with respect to said screens and catalytic material,whereby the exhaust gases are constrained to pass through said catalyticmaterial in passing I through the exhaust container from said exhaustinlet ipe to said outlet.

2. An ex aust container for an internal combustion engine, comprising acasin having discharge outlet, an inlet pipe therein provided with anexhaust opening, spaced wportions of catalytic material surrounding saidpipe on opposite sides of said exhaust opening and inter osed betweensaid exhaust opening an said discharge outlet, and foraminous retainersfor said catalytic portions, the construction being such that theexhaust gases discharged from said exhaust opening divide, a portion ofthe exhaust gases passing through said foraminous retainer and catalyticportion on one side of said exhaust opening, and another portion of theexhaust gases pasing through said foraminous retainer and catalyticportion on the other side of said exhaust opening. I

3. An exhaust container for an internal combustion engine, comprisingacasing having an inlet and an outlet, an inlet pipe connected to saidinlet and extending within said casing, said inlet pipe having anexhaust opening therein, and a plurality of spaced-apart portions ofcatalytic material adapted to further a secondary combustion of saidexhaust gases interposed in parallel between said exhaust opening andsaid outlet.

4. An exhaust container for an internal combustion engine, comprising acylindrical casing having an inlet and an outlet, an

inlet pipe connected to said inlet and extending within said casing, acylindrical jacket spaced within said casing, said jacket havingopenings therein communicating with the space within said casing andwith said outlet, and a plurality of spaced apart portions of catalyticmaterial confined between said jacket and said inlet pipe and forming aplurality of chambers about said pipe which communicate through saidcatalytic material with the openings in said jacket, said inlet pipehaving a p urality of openin s providing communication with each 0 saidchambers.

5. An exhaustcontainer for an internal combustion engine, comprising acasing having an inlet'at one end thereof and an outlet adjacent theother end thereof, an inlet pipe connected to said inlet and extendingwithin said casing toward said outlet end, said pipe having a pluralityof openings along the length thereof, a plurality of spaced portions ofcatalytic material interposed between said openings and said outlet,said pipe also having an opening communicating directly with saidoutlet, a valve for controlling said last mentioned opening, and meansfor actuating said valve,

In testimony whereof I have afiixed my signature.

DR. WILHELM RIEHM.

